Article Of Footwear Having A Flexible Fluid-Filled Chamber

ABSTRACT

An article of footwear may include an upper forming a void within the footwear, a sole structure secured to the upper, and a chamber that encloses a pressurized fluid. The sole structure includes a depression. The chamber is located within the void of the upper and located on the depression of the sole structure. The chamber may include a plurality of fluid-filled subchambers, a manifold, and a connection fluidically-connected at least one of the subchambers to the manifold. The subchambers may enclose the pressurized fluid at different pressures. The subchambers may be separated from one another by a bonded area in the direction extending between the heel and toe of the chamber.

BACKGROUND

Articles of footwear generally include two primary elements: an upperand a sole structure. The upper is often formed from a plurality ofmaterial elements (e.g., textiles, polymer sheet layers, polymer foamlayers, leather, synthetic leather) that are stitched or adhesivelybonded together to form a void within the footwear for comfortably andsecurely receiving a foot. More particularly, the upper forms astructure that extends over instep and toe areas of the foot, alongmedial and lateral sides of the foot, and around a heel area of thefoot. The upper may also incorporate a lacing system to adjust the fitof the footwear, as well as permitting entry and removal of the footfrom the void within the upper. In addition, the upper may include atongue that extends under the lacing system to enhance adjustability andcomfort of the footwear, and the upper may incorporate a heel counterfor stabilizing the heel area of the foot.

The sole structure is secured to a lower portion of the upper andpositioned between the foot and the ground. In athletic footwear, forexample, the sole structure often includes a midsole and an outsole. Themidsole may be formed from a polymer foam material that attenuatesground reaction forces (i.e., provides cushioning) during walking,running, and other ambulatory activities. The midsole may also includefluid-filled chambers, plates, moderators, or other elements thatfurther attenuate forces, enhance stability, or influence the motions ofthe foot, for example. In some configurations, the midsole may beprimarily formed from a fluid-filled chamber. The outsole forms aground-contacting element of the footwear and is usually fashioned froma durable and wear-resistant rubber material that includes texturing toimpart traction. The sole structure may also include a socklinerpositioned within the void of the upper and proximal a lower surface ofthe foot to enhance footwear comfort.

One manner of reducing the weight of a polymer foam midsole anddecreasing the effects of deterioration following repeated compressionsis disclosed in U.S. Pat. No. 4,183,156 to Rudy, hereby incorporated byreference, in which ground reaction force attenuation is provided by afluid-filled chamber formed of an elastomeric material. The chamberincludes a plurality of tubular chambers that extend longitudinallyalong a length of the sole structure. The chambers are in fluidcommunication with each other and jointly extend across the width of thefootwear. The chamber may be encapsulated in a polymer foam material, asdisclosed in U.S. Pat. No. 4,219,945 to Rudy, hereby incorporated byreference. The combination of the chamber and the encapsulating polymerfoam material functions as a midsole. Accordingly, the upper is attachedto the upper surface of the polymer foam material and an outsole ortread member is affixed to the lower surface. Chambers of the typediscussed above are generally formed of an elastomeric material and arestructured to have an upper and lower portions that enclose one or morechambers therebetween. The chambers are pressurized above ambientpressure by inserting a nozzle or needle connected to a fluid pressuresource into a fill inlet formed in the chamber. Following pressurizationof the chambers, the fill inlet is sealed and the nozzle is removed.

Fluid-filled chambers suitable for footwear applications may bemanufactured by a flat-film bonding technique, in which two separatepolymer sheets, possibly an elastomeric film, are bonded together alongtheir respective peripheries to form a sealed structure, and the sheetsare also bonded together at predetermined interior areas to give thechamber a desired configuration. That is, the interior bonds provide thechamber with a predetermined shape and size when inflated. In athermoforming process, the sheets may also be heated and molded toimpart a pre-determined shape. Such chambers have also been manufacturedby blowmolding, wherein a molten or otherwise softened elastomericmaterial in the shape of a tube is placed in a mold having the desiredoverall shape and configuration of the chamber. The mold has an openingat one location through which pressurized air is provided. Thepressurized air induces the liquefied elastomeric material to conform tothe shape of the inner surfaces of the mold. The elastomeric materialthen cools, thereby forming a chamber with the desired shape andconfiguration.

SUMMARY

According to one configuration, an article of footwear may include anupper forming a first portion of a void within the footwear. The articleof footwear may further include a sole structure secured to the upper.The sole structure may include a depression that forms a second portionof the void. The article of footwear may further include a chamber thatencloses a pressurized fluid. The chamber may be located within thedepression. The chamber may include a plurality of fluid-filledsubchambers that extend in a medial to lateral direction of thefootwear. At least two of the subchambers may be isolated from fluidcommunication with each other.

According to another configuration, an article of footwear includes anupper forming a first portion of a void within the footwear. The uppermay include an ankle opening that provides access to the void. Thearticle of footwear may further include a sole structure secured to theupper. The sole structure may include a depression that forms a secondportion of the void. The article of footwear may further include achamber that encloses a pressurized fluid. The chamber may be locatedwithin the depression. The article of footwear may further include aninsert located on a top surface of the chamber and being at leastpartially formed from a polymer foam material. The chamber and theinsert may be removable from the void through the ankle opening.

According to another configuration, a method of manufacturing a chamberenclosing a pressurized fluid includes placing a first sheet and asecond sheet within a mold. The mold is closed to form a bonded areabetween the first sheet and the second sheet and at least one chamber,wherein the chamber includes a plurality of subchambers and a manifoldfluidically-connected to at least two of the subchambers. A pressurizedfluid is supplied at a first pressure to the manifold so that the twosubchambers are inflated with the pressurized fluid. A connectionfluidically-connecting the manifold to a first subchamber of the twosubchambers is first sealed to seal the pressurized fluid within thefirst subchamber. A pressurized fluid is supplied at a second pressureto the manifold so that a second subchamber of the two subchambers isinflated with the pressurized fluid. A connection fluidically-connectingthe manifold to the second subchamber is second sealed to seal thepressurized fluid within the second subchamber.

According to another configuration, an article of footwear may includean upper, a sole structure, and a chamber. The upper may form a firstportion of a void within the footwear. The upper may include an ankleopening that provides access to the void. The sole structure may besecured to the upper. The sole structure may include a depression thatforms a second portion of the void. The chamber may enclose apressurized fluid. The chamber may be located within the depression. Thechamber may include a plurality of fluid-filled subchambers that extendin a medial to lateral direction of the footwear. The chamber mayinclude a manifold in fluid communication with the subchambers. Thechamber may include bonds that extend in the medial to lateral directionand are located between the subchambers. The chamber may be removablefrom the article of footwear through the ankle opening.

The advantages and features of novelty characterizing aspects of theinvention are pointed out with particularity in the appended claims. Togain an improved understanding of the advantages and features ofnovelty, however, reference may be made to the following descriptivematter and accompanying figures that describe and illustrate variousconfigurations and concepts related to the invention.

FIGURE DESCRIPTIONS

The foregoing Summary and the following Detailed Description will bebetter understood when read in conjunction with the accompanyingfigures.

FIG. 1 is a side elevational view of an article of footwear.

FIG. 2 is a cross-sectional view of the article of footwear along line2-2 of FIG. 1.

FIGS. 3A-3C are side elevational views of a process of removing afluid-filled chamber from the article of footwear

FIG. 4 is a perspective view of the chamber.

FIG. 5 is a top plan view of the chamber.

FIG. 6 is a side elevational view of the chamber.

FIG. 7 is a perspective view of a mold for manufacturing a fluid-filledchamber.

FIG. 8 is a top plan view of a portion of the mold.

FIG. 9 is a cross-sectional view of the portion of the mold along line9-9 of FIG. 8.

FIGS. 10A-10C are perspective views of a chamber manufacturing processutilizing the mold.

FIGS. 11A-11D are cross-sectional views of the chamber manufacturingprocess along line 11-11 in FIG. 10A.

FIG. 12 is a top plan view of a product from the mold.

FIG. 13 is a perspective view of a fluid-filled chamber with an insert.

FIG. 14 is a perspective view of the insert.

FIG. 15 is a cross-sectional view of an article of footwear includingthe fluid-filled chamber and the insert from FIG. 13.

FIG. 16 is a perspective view of an article of footwear.

FIG. 17 is an exploded perspective view of the article of footwear ofFIG. 16.

FIG. 18 is a top plan view of a product of a molding process to producea fluid-filled chamber.

FIG. 19 is a top plan view of a fluid-filled chamber.

FIG. 20 is a top plan view of a fluid-filled chamber.

DETAILED DESCRIPTION

The following discussion and accompanying figures disclose variousconfigurations of an article of footwear having a sole structure.Although the footwear is disclosed as having a configuration that issuitable for running, concepts associated with the footwear may beapplied to a wide range of athletic footwear styles, includingbasketball shoes, cross-training shoes, football shoes, golf shoes,hiking shoes and boots, ski and snowboarding boots, soccer shoes, tennisshoes, and walking shoes, for example. Concepts associated with thefootwear may also be utilized with footwear styles that are generallyconsidered to be non-athletic, including dress shoes, loafers, andsandals. Accordingly, the concepts disclosed herein may be utilized witha variety of footwear styles.

An article of footwear 100 is depicted in FIG. 1 as including an upper110 and a sole structure 120. Upper 110 provides a comfortable andsecure covering for a foot of a wearer. As such, the foot may be locatedwithin upper 110 to effectively secure the foot within footwear 100.Sole structure 120 is secured to a lower area of upper 110 and extendsbetween upper 110 and the ground. When the foot is located within upper110, sole structure 120 extends under the foot to attenuate groundreaction forces (i.e., cushion the foot), provide traction, enhancestability, and influence the motions of the foot, for example.

For purposes of reference in the following discussion, footwear 100 maybe divided into three general regions: a forefoot region 102, a midfootregion 103, and a heel region 104. Forefoot region 102 generallyincludes portions of footwear 100 corresponding with the toes and thejoints connecting the metatarsals with the phalanges. Midfoot region 103generally includes portions of footwear 100 corresponding with an archarea of the foot. Heel region 104 generally corresponds with rearportions of the foot, including the calcaneus bone. Footwear 100 alsoincludes a medial side 106 and a lateral side 108, as shown in FIG. 2,which extend through each of regions 102-104 and correspond withopposite sides of footwear 100. More particularly, lateral side 108corresponds with an outside area of the foot (i.e. the surface thatfaces away from the other foot), and medial side 106 corresponds with aninside area of the foot (i.e., the surface that faces toward the otherfoot).

Regions 102, 103, 104 and sides 106, 108 are not intended to demarcateprecise areas of footwear 100. Rather, regions 102, 103, 104 and sides106, 108 are intended to represent general areas of footwear 100 to aidin the following discussion. In addition to footwear 100, regions 102,103, 104 and sides 106, 108 may also be applied to upper 110, solestructure 120, and individual elements thereof.

Upper 110 is depicted as having a substantially conventionalconfiguration formed from a variety of elements (e.g., textiles, polymersheet layers, polymer foam layers, leather, synthetic leather) that arestitched, bonded, or otherwise joined together to provide a structurefor receiving and securing the foot relative to sole structure 120. Thevarious elements of upper 110 define a portion of a void 111 withinfootwear 100 that is intended to receive the foot. As such, upper 110extends along the lateral side 108 of the foot, along the medial side106 of the foot, over the foot, around a heel of the foot, and under thefoot. Access to void 111 is provided by an ankle opening 112 located inat least the heel region 104 of the footwear 100. A lace 114 extendsthrough various lace apertures 116 and permits the wearer to modifydimensions of upper 110 to accommodate the proportions of the foot. Moreparticularly, lace 114 permits the wearer to tighten upper 110 aroundthe foot, and lace 114 permits the wearer to loosen upper 110 tofacilitate entry and removal of the foot from void 111 (i.e., throughankle opening 112). As an alternative to lace apertures 116, upper 110may include other lace-receiving elements, such as loops, eyelets,hooks, and D-rings. In addition, upper 110 includes a tongue 118 thatextends between void and lace 114 to enhance the comfort andadjustability of footwear 100. In some configurations, upper 110 mayincorporate other elements, such as reinforcing members, aestheticfeatures, a heel counter that limits heel movement in the heel of thefootwear, a wear-resistant toe guard located in the forefoot of thefootwear, or indicia (e.g., a trademark) identifying the manufacturer.Accordingly, upper 110 is formed from a variety of elements that form astructure for receiving and securing the foot.

Turning to FIG. 2, the primary elements of sole structure 120 are afluid-filled chamber or chamber 130 and an outer sole 140. Chamber 130may be, for example, a sealed fluid-filled chamber containing apressurized fluid, which will be discussed below. Moreover, chamber 130is (a) located within a portion of void 111 that is formed by outer sole140 and (b) positioned to extend under and support a foot located withinthe other portion of void 111.

Outer sole 140 includes a body portion 141 and a ground-engagementportion 142. Body portion 141 has a generally concave configurationforming a depression in outer sole 140 that extends through regions102-104 and sides 106, 108, thereby extending through a majority of alength and width of sole structure 120. The depression forms the portionof void 111 that receives chamber 130. As such, a surface of thedepression has a shape corresponding to the general shape of chamber130. Thus, upper 110 and outer sole 140 may cooperate to provide void111 with a shape that accommodates both the foot of the wearer andchamber 130. Ground engagement portion 142 is secured to a lower surfaceof body portion 141 and is textured to enhance the traction (i.e.,friction) properties between footwear 100 and the ground. Although notdepicted, sole structure 120 may further include a sockliner that ispositioned upon an upper surface of chamber 130. The sockliner may be acompressible member located within void 102 and adjacent a lower surfaceof the foot to enhance the comfort of footwear 100. In configurationswhere a sockliner is not utilized, the foot may rest directly upon anupper surface of chamber 130, or a textile (e.g., non-woven textile) maybe secured to the upper surface of chamber 130.

Turning to FIG. 3A, chamber 130 may extend within footwear 100 betweenforefoot region 102 and heel region 104. Chamber 130 may be insertedwithin footwear 100 to provide cushioning and support to a foot insertedwithin footwear 100. As shown in the examples of FIGS. 3B and 3C,chamber 130 may be inserted or removed through ankle opening 112 indirection 10. Because chamber 130 may be inserted within and removedfrom footwear 100, chamber 130 may be replaceable. For example, chamber130 may be removed from upper 110, such as by a user of footwear 100,and replaced by another chamber, when chamber 130 has become worn. Inanother example, chamber 130 may be modular and may be removed fromupper 110, such by a user of footwear 100, and replaced by a chamberhaving different properties, such as a different amount of cushioningand support suitable for a desired activity.

According to another embodiment, chamber 130 may be secured to a lowerarea of upper 110 and may replace a strobel material that isconventionally utilized in footwear lasting processes. That is, asurface of chamber 130 or a polymer flange extending outward from edgesof chamber 130 may be secured to the lower area of upper 110. In someconfigurations, an opposite surface of chamber 130 may be secured toouter sole 140. In such an example, a lower portion of upper 110 may bedirectly attached to chamber 130 instead of to body portion 141 of outersole 140. Outer sole 140 may then be formed around chamber 130 toprovide a ground contacting surface. Although a sockliner may extendbetween the foot and chamber 130, the foot may rest directly upon anupper surface of chamber 130, or a textile (e.g., non-woven textile) maybe secured to the upper surface of chamber 130.

FIGS. 4-6 show an exemplary configuration of chamber 130, which issealed to contain a pressurized fluid. When incorporated into footwear100, chamber 130 may have a shape that fits within a perimeter of solestructure 120 (i.e., within the depression in outer sole 140) andsubstantially extends from forefoot region 102 to heel region 104 andalso from lateral side 108 to medial side 106, thereby correspondingwith a general outline of the foot. When the foot is located withinupper 110, chamber 130 extends under substantially all of the foot inorder to attenuate ground reaction forces that are generated when solestructure 120 is compressed between the foot and the ground duringvarious ambulatory activities, such as running and walking. In anotherconfiguration, midsole 122 may include additional materials orcomponents, such as, for example, foam. Although chamber 130 is locatedwithin outer sole 140, portions of body portion 141 may form aperturesor other openings that expose areas of chamber 130. As such, chamber 130may form a portion of the sidewall of footwear 100 in someconfigurations. In other configurations, chamber 130 may extend underonly a portion of the foot.

Chamber 130 may include one or more subchambers 132 that enclose thepressurized fluid, thereby providing cushioning and support to the foot.Subchambers 132 may be defined by a bonded area 138 that surroundssubchambers 132, as shown in the example of FIG. 5. Bonded area 138 mayextend around chamber 130 to form a sealed perimeter of chamber 130.Bonded area 138 may also extend between subchambers 132, as shown inFIG. 5, to separate subchambers 132 from one another. More particularly,portions of bonded area 138 are oriented in a direction that extendsbetween sides 106, 108 to separate portions of bonded area 138 andprevent the fluid from passing between adjacent subchambers 132. Theportions of bonded area 138 located between subchambers 132 are alignedin a direction extending through each of regions 102-104, thereby beinglocated between the heel and toe of chamber 130. A majority of chamber130 may be provided by subchambers 132. For instance, subchambers 132may provide approximately 80% or more of the volume of chamber 130. Inanother example, subchambers 132 may provide approximately 90% or moreof the volume of chamber 130.

Bonded areas 138 located in between each subchamber 132 may provide arelatively thin portion of chamber 130 in comparison to a thickness ofeach subchamber 132, as shown in FIG. 6. As a result, the bonded area138 in between each subchamber 132 may not only separate individualsubchambers from one another but also provide areas of enhancedflexibility for chamber 130, permitting chamber 130 to bend andcorrespond to movements to a foot within footwear 100.

Subchambers 132 may have a uniform size or may vary in size. Forexample, as shown in FIG. 6, subchambers 132 in midfoot region 173 andin heel region 172 may have a larger cross-sectional shape or a largerdiameter than subchambers 132 in forefoot region 174. In anotherexample, subchambers 132 in heel region 172 may have a largercross-sectional shape or diameter than subchambers 132 in midfoot region173 and subchambers 132 in forefoot region 174, and subchambers 132 inforefoot region 174 may have a larger cross-sectional shape or diameterthan subchambers 132 in midfoot region 173. In another example,subchambers 132 in midfoot region 173 may have a larger cross-sectionalshape or diameter than subchambers 132 in heel region 172 andsubchambers 132 in forefoot region 174.

Subchambers 132 can be in the form of tubes that extend in a directionbetween medial side 106 and lateral side 108 of chamber 130, as shown inFIG. 5. Subchambers 132 may have a shape other than the shape of a tube,such as, for example, a circular, rectangular, or other shape. In oneconfiguration, subchambers 132 may have a substantially roundcross-section, as shown in the example of FIG. 6. In otherconfigurations, subchambers 132 may have various cross-sections, suchas, for example, a circular, oval, rectangular, or other shape.

To provide pressurized fluid to each of the individual subchambers 132and inflate subchambers 132, chamber 130 may include a manifold 134 thatdistributes the pressurized fluid to subchambers 132. Manifold 134 maybe connected to a conduit external to chamber 130 (not shown) thatsupplies the pressurized fluid to the manifold during an inflationprocess, as will be discussed below. Manifold 134 may be on medial side106 of chamber 130, as shown in the example of FIG. 5, or may be locatedon lateral side 108 of chamber 130.

To distribute the pressurized fluid to subchambers, manifold 134 may befluidically-connected to the subchambers by connections. As shown in theexample of FIG. 5, manifold 134 may be connected to individualsubchambers 132 by connections 136. In another configuration, aconnection may connect more than one subchamber to manifold. Forinstance, two, three, or four or more subchambers 132 may be connectedto manifold 134 with a single connection 136.

According to an embodiment, chamber 130 may include a layer or coatingon its outer surface. Such a layer or coating may be used, for example,to alter the surface texture or roughness of chamber 130 so that chamberis less smooth. For instance, a layer or coating may be applied tochamber 130 to make chamber 130 feel more like a fabric. Such a layer orcoating may be, for example, a textile having a configuration of aknitted, woven, or non-woven material. In a further example, a layer orcoating may be a non-woven thermoplastic polyurethane (TPU). Byproviding chamber 130 with a layer or coating, a sockliner that mayotherwise be placed on top of chamber 130 within an article of footwearmay be unnecessary. Thus, a chamber 130 with a layer or coating appliedor bonded to its surface may be placed within an article of footwearwithout a sockliner so that a foot inserted within the article offootwear directly contacts chamber 130. Although various methods may beutilized to bond a textile to chamber 130, the textile may be placedwithin a mold (see discussion below) that forms chamber 130 and bondedto chamber 130 during a molding process.

Turning to FIG. 7, a configuration of a mold 200 for molding a pair ofchambers is shown. Mold 200 may include a first mold section 210 and asecond mold section 212 to mold chambers as described herein. First moldsection 210 may include a first region 202 and a second region 204.First region 202 and second region 204 may have shapes corresponding toa desired shape and features of chamber 130, including subchambers 132,manifold 134, connections 136, and bonded areas 138. Second mold sectionmay include a first region 214 that corresponds to first region 202 offirst mold section 210 and a second region 216 that corresponds tosecond region 204 of first mold section 210 for molding a first chamberand a second region 204 for molding a second chamber. As shown in FIGS.7 and 8, first region 202 and second region 204 of first mold section210 may include recesses that correspond to subchambers 132 of chamber130, although any number of recesses may be provided to correspond to adesired number of subchambers in a chamber. First region 202 and secondregion 204 also include recesses which correspond to connections 136 ofchamber 130 and recesses 203, 205, respectively, which each correspondto manifold 134 of chamber 130. FIG. 9 depicts a cross-sectional view ofmold half 200 along line 9-9 of FIG. 8 and shows another view of therecesses of second portion 204.

Portions of first mold section 210 and second mold section 212 that donot include a recess may serve to form bonded area 170 of chamber 130,such as between subchambers 132 of chamber 130 and a bonded areasurrounding an outer perimeter of chamber 130. For example, portions ofmold 200 located outside of first region 202 and second region 204 offirst mold half 210 and located outside of first region 214 and secondregion 216 of second mold section 212 may be configured to form bondedarea 170 of chamber 130.

Mold 200 may further include areas that form a conduit so thatpressurized fluid may be supplied to chambers after being molded. Asshown in the example of FIG. 8, a main indentation 206 may be providedin first mold section 210 to form a main conduit 506 in a molded product500, which will be discussed below in regard to FIG. 12. During asubsequent inflation process after molding is complete, main conduit 506receives a pressurized fluid to inflate molded product 500 and form achamber. Main indentation 206 branches into a secondary indentation 207to form a secondary conduit 507 in molded product 500. Main indentation206 also branches into a secondary indentation 208 to form a secondaryconduit 508 in molded product 500. Second mold section 212 may haveindentations corresponding to those of first mold section 210 so thatfirst mold section and second mold section 212 cooperate to mold themain and secondary conduits of molded product 500. Secondary indentation207 fluidically-connects with recess 203 and secondary indentation 208fluidically-connects with recess 205.

Turning to FIGS. 10A-11D, an exemplary process is explained forproducing a chamber according to the configurations discussed herein. Aprocess for manufacturing a chamber may be, for example, twin sheetthermoforming or another process used in the art, such as a flat-filmbonding technique or blowmolding. As shown in FIG. 10A, first moldsection 210 and second mold section 212 may be provided. A first sheet300 and a second sheet 302 may be placed between first mold section 210and second mold section 212, as shown in FIG. 10A. First sheet 300 andsecond sheet 302 may be provided as lower and upper barrier layers for achamber and may be made from the materials described below for barrierlayers.

As shown in FIG. 10B, first mold section 210 and second mold section 212may be closed together to bond first sheet 300 and second sheet 302. Forexample, when chamber 130 is being formed, first mold section 210 andsecond mold section 212 may cooperate to bond first sheet 300 and secondsheet 302 together to form bonded area 170 of chamber 130. Further, atleast one of first mold section 210 and second mold section 212 mayinclude main indentation 206 and secondary indentations 207, 208 tosupply pressurized fluid and inflate subchambers 132 within recesses(not shown but discussed below) of first mold section 210 and secondmold section 212, as well as connections 136 and manifold 150. Oncebonding is complete, first mold section 210 and second mold section 212may be separated to release a molded product 500 formed from first sheet300 and second sheet 310, as shown in FIG. 10C. Molded product 500 issubsequently supplied with pressurized fluid to be inflated and form achamber.

During the bonding process, first sheet 300 and second sheet 302 areformed to have the general shape of mold sections 210, 212 and bondedtogether. Turning to FIG. 11A, which is a side cross-sectional viewtaken along line 11-11 of FIG. 10A, first mold section 210 may includerecesses 211 and second mold section 212 may include recesses 213.Recesses 211, 213 may cooperate to provide a shape corresponding tosubchambers 132 of chamber 130. Subsequently, first mold section 210 andsecond mold section 212 may be closed together, with first sheet 300 andsecond sheet 302 in between. Further, if a chamber formed from firstsheet 300 and second sheet 302 is to include a layer or coating on itssurface, as discussed above, one or more sheets of material (not shown)may be placed between first sheet 300 and mold section 212 and/orbetween second sheet 302 and mold section 210 to apply the material as alayer or coating during the bonding process.

Next, first sheet 300 and second sheet 302 are deformed to the surfaceof mold sections 210, 212. Mold sections 210, 212 may be heated so thatsheets 300, 302 are in turn heated and softened to assist with thedeformation of sheets 300, 302. A fluid may be supplied between firstsheet 300 and second sheet 302. In particular, the fluid may be suppliedto unbounded areas of first sheet 300 and second sheet 302 locatedwithin recesses 211, 213. The fluid may be used to force first sheet 300and second sheet 302 towards surfaces of mold sections 210, 212 so thatthe fluid assists with the deformation of sheets 300, 302 to the shapeof mold sections 210, 212. For example, fluid may be supplied via mainindentation 206 and secondary indentations 207, 208 formed in either orboth of first mold section 210 and second mold section 212, as shown inFIG. 8. In addition, air may be withdrawn from between sheets 300, 302and mold sections 210, 212 to assist with deforming sheets 300, 302 tothe general shape of mold sections 210, 212, particularly the shape ofrecesses 211, 213. Because the portions of first sheet 300 and secondsheet 302 located within recesses 211, 213 are not bonded to oneanother, fluid supplied to recesses 211, 213 cause these portions offirst sheet 300 and second sheet 302 to separate and generally adapt theshape of recesses 211, 213, as shown in FIG. 11C. These unbondedportions of first sheet 300 and second sheet 302 within recesses 211,213 may be formed as subchambers 132 of chamber 130 during a subsequentinflation operation (not shown) after bonding is complete. Finally, whenthe molding process is complete, first mold section 210 and second moldsection 212 may be separated to release a molded product 500, as shownin FIG. 11D.

During the subsequent inflation of subchambers 132, the pressure of thefluid within subchambers 132 may be selectively controlled. In oneconfiguration, a pressure of the pressurized fluid contained withinsubchambers 132 may be substantially uniform, with the pressurized fluidwithin each of subchambers 132 being at substantially the same pressure.For example, the pressure within chamber 130 (and within each of theindividual subchambers 132) may be from approximately 0-14 psi(approximately 0-97 kPa). In another example, the pressure with each ofthe individual subchambers 132 may be from approximately 2-14 psi(approximately 13-97 kPa).

In another configuration, the pressures of the fluid within subchambers132 may be advantageously selected and varied to provide a desiredamount of cushioning and support for different portions of a foot. Forexample, the pressure of subchambers in heel region 172 may be selectedto be greater than the pressure of subchambers in forefoot region 174 toprovide greater cushioning and support to a heel portion of a foot. Forinstance, subchambers 132 in heel region 172 may have a pressure ofapproximately 7-10 psi (approximately 48-69 kPa), while subchambers 132in forefoot region 174 may have a pressure of approximately 3-5 psi(approximately 20-34 kPa). The pressurized fluid within the subchambersof heel region 172 may also be at a higher pressure than the subchambersof midfoot region 173. For example, the pressure of subchambers in heelregion 172 may be selected to be greater than the pressure ofsubchambers in both the forefoot region 174 and the midfoot region 173.In another example, the pressure of subchambers in heel region 172 maybe selected to be greater than the pressure of subchambers in both theforefoot region 174 and the midfoot region 173, and the pressure ofsubchambers in the forefoot region 174 may be greater than the pressureof subchambers in the midfoot region 173 to provide greater cushioningand support to the heel and forefoot portions of a foot. For instance,subchambers 132 in heel region 172 may have a pressure of approximately9-12 psi (approximately 62-83 kPa), subchambers 132 in midfoot region173 may have a pressure of approximately 2-4 psi (approximately 14-28kPa), and subchambers 132 in forefoot region 174 may have a pressure ofapproximately 5-7 psi (approximately 34-48 kPa).

In another configuration, the pressure of the pressurized fluid may varyfrom subchamber to subchamber. For example, the pressure in subchambers132 may decrease from the heel to the forefoot of the chamber 130. Inanother example, subchambers 132 in heel region 172 may each have adifferent pressure that is higher than the pressures of subchambers 132in midfoot region 173, and subchambers 132 in forefoot region 174 mayeach have a different pressure that is higher than the pressures ofsubchambers 132, which also vary.

Variations in pressure from region to region or subchamber to subchambermay be accomplished by selective sealing of the connections between thesubchambers and the manifold. For example, pressurized fluid may besupplied to manifold 134 at a first pressure and the pressurized fluidmay be then be supplied to subchambers 132 via connections 136. As aresult, subchambers 132 are supplied with the pressurized fluid at thefirst pressure. If it is desired that one or more regions or subchambersbe pressurized to a greater pressure than another region or subchamber,selected connections between the subchambers and the manifold may becarried out.

For example, a process can be utilized for providing subchambers 132 inmidfoot region 173 with pressurized fluid at a pressure of approximately2-4 psi (approximately 14-28 kPa), subchambers 132 in forefoot region174 with a pressurized fluid at a pressure of approximately 5-7 psi(approximately 34-48 kPa), and subchambers 132 in heel region 172 withpressurized fluid at approximately 9-12 psi (approximately 62-83 kPa).First, the pressurized fluid at a pressure of approximately 2-4 psi(approximately 14-28 kPa) may be first supplied to all of subchambers132 via manifold 134 and connections 136. Second, connections 136 thatconnect subchambers 132 of midfoot region 173 to manifold 134 may besealed to enclose the pressurized fluid at approximately 2-4 psi withinsubchambers 132 in midfoot region 173. Third, the supplied pressurizedfluid may be increased in pressure to approximately 5-7 psi(approximately 34-48 kPa) so that subchambers 132 in forefoot region 174and subchambers 132 in heel region 172 include pressurized fluid atapproximately 5-7 psi (approximately 34-48 kPa). Fourth, connections 136that connect subchambers 132 to manifold 134 may be sealed to enclosethe pressurized fluid at approximately 5-7 psi within subchambers 132 inforefoot region 174. Fifth, the supplied pressurized fluid may beincreased in pressure to approximately 9-12 psi (approximately 62-83kPa) so that subchambers 132 in heel region 172 include pressurizedfluid at approximately 9-12 psi (approximately 62-83 kPa). Next,connections 136 that connect subchambers 132 to manifold 134 may besealed to enclose pressurized fluid at approximately 9-12 psi(approximately 62-83 kPa) within subchambers 132 in heel region 172.

In another example, instead of sealing individual connections tosubchambers 132, manifold 134 itself may be sealed. For instance, ifpressurized fluid is supplied to manifold 134 from an end of manifold134 in heel region 104 and the pressurized fluid flows along manifold134 from heel region 104 to midfoot region 103 and then to forefootregion 102, manifold 134 may be sealed between midfoot region 103 andforefoot region 102 after a desired pressure of the pressurized fluidhas been supplied to forefoot region 102. Subsequently, after a desiredpressure of the pressurized fluid has been supplied to midfoot region103, manifold may be sealed between heel region 104 and midfoot region103. Finally, once a desired pressure has been supplied to subchambers132 of heel region 104, manifold 134 may be sealed.

The exemplary processes described above may be modified to provideregions 172-174 with different pressures or to provide individualsubchambers 132 with specific, desired pressures. For example, ifspecific pressures are desired for each of subchambers 132, any ofconnections 136 may be individually sealed after supplying a desiredpressure to manifold 134, thus providing a particular pressure to eachof subchambers 132.

Other processes may be used to manufacture chamber 130. For example,chamber 130 may be formed via a flat-film bonding process, in whichfirst sheet 300 and second sheet 302 are bonded together along theirrespective peripheries to form a sealed structure, and sheets 300 and302 are also bonded together at predetermined interior areas to givechamber 130 and each of subchambers 132 a desired configuration. Thatis, the interior bonds provide chamber 130 with a predetermined shapeand size when inflated. Blowmolding may also be utilized to form chamber130, wherein a molten or otherwise softened elastomeric material in theshape of a tube is placed in a mold having the desired overall shape andconfiguration of chamber 130. Pressurized air induces the liquefiedelastomeric material to conform to the shape of the inner surfaces ofthe mold. The elastomeric material then cools, thereby forming chamber130 to have the desired shape and configuration.

A configuration of a product 500 of a molding process is depicted inFIG. 12. Product 500 may be in the general form of a sheet that includesa first chamber 502 and a second chamber 504 that have each beeninflated and sealed to contain a pressurized fluid. First chamber 502and second chamber 504 may be contained within a bonded area 510 thatsurrounds first chamber 502 and second chamber 504. Such a bonded area510 may be provided, for example, by bonding first sheet 400 and secondsheet 402 in the process described above. Each of first chamber 502 andsecond chamber 504 may include any number of subchambers andconnections, as described for chamber 130, for example. Product 500 mayinclude a main conduit 506 through which the pressurized fluid wassupplied, as well as a secondary conduit 507 and a secondary conduit 508that are respectively fluidically-connected to manifold 503 of firstchamber 502 and manifold 505 of second chamber 504.

Once molding of product 500 has been completed, a seal may be providedwithin main conduit 506, and/or secondary conduits 507, 508, and/or atan opening to manifolds 503, 505 to seal the pressurized fluid withinchamber 502 and chamber 504. After sealing has been completed, firstchamber 502 and second chamber 504 may be removed from the general sheetform of product 500, such as by cutting off the bonded area 510surrounding first chamber 502 and second chamber 504.

Further Configurations

According to one configuration, a chamber may include additionalcomponents. For example, a chamber may include one or more components toaffect the fit of the chamber to a foot and/or the support provided bythe chamber. Turning to FIG. 13, a foot-supporting system 600 mayinclude a fluid-filled chamber 610, which may have the features of anyof the chamber configurations described herein, and an insert 620.Insert 620 may also provide lateral support and stability to the footinserted within footwear 100 by providing support on each side of thefoot. Insert 620 may be made of foam, fabric, or any combination ofmaterials. Insert 620 may be joined to fluid-filled chamber 610 or maybe separate from fluid-filled chamber 610.

As shown in the example of FIG. 13, insert 620 may be located on a topsurface of fluid-filled chamber 610. FIG. 15 shows an example offluid-filled chamber 610 inserted within an upper 710 and on top of anoutsole 740, with insert 620 located on a top surface of fluid-filledchamber 610. According to another configuration, insert 620 may belocated on a bottom surface of fluid-filled chamber 610, such as betweenfluid-filled chamber 610 and outsole 740.

Insert 620 may include structures to assist with fitting or joininginsert 620 to fluid-filled chamber 610. Insert 620 may include one ormore indentations 622, 624, 626 that project downwards towards afluid-filled chamber, as shown in FIGS. 13 and 14. Indentations 622,624, 626 may have locations and shapes corresponding to subchambers of afluid-filled chamber. For example, indentations 622, 624, 626 may havelocations and shapes corresponding to subchambers 132 of chamber 130 inFIG. 5. In addition, insert may include projections 623, 625 betweenindentations 622, 624, 626 to assist with fitting or joining insert 620to fluid-filled chamber 610. Projections 623, 625 may be positioned tomatch the locations of bonded areas between subchambers of afluid-filled chamber. For example, projections 623, 625 may correspondto the locations of bonded areas 170 between subchambers 132 of chamber130 in FIG. 5. As a result, insert 620 may include indentations 622,624, 626 and projections 623, 625 having locations and shapes thatcorrespond to a surface of a fluid-filled chamber and thus assist to fitor join insert 620 to the fluid-filled chamber.

Other alternative arrangements and configurations for a chamber may beprovided. For example, a chamber may be located outside of a void withinan article of footwear. As shown in FIG. 16, an article of footwear 1100may include an upper 1110 and a sole structure 1120. However, instead oflocating a chamber 1122 within a void that is at least partially formedby upper 1110, as with chamber 130 shown in FIG. 2, chamber 1122 may belocated inside a midsole 1123 that is secured to a bottom surface ofupper 1110, as shown in FIG. 17. Chamber 1122 may be provided as afluid-filled chamber according to the configurations described hereinand may be provided in combination with other components discussedherein. For instance, chamber 1122 may include all of the features ofchamber 130. Chamber 1122 may be provided as a fluid-filled chamber incombination with foam, such as a fluid-filled chamber 1122 encapsulatedin foam to provide midsole 1123 that is joined to a bottom surface ofupper 1110. An outsole 1124 may also be provided on a bottom surface ofchamber 1122, as shown in the example of FIG. 17.

According to one configuration, a chamber may include a plurality ofmanifolds connected to subchambers. Turning to FIG. 18, a product 800 ofa molding process may include a first chamber 802 and a second chamber804 surrounded by a bonded area 850. First chamber 802 may includemanifolds 820-823 and second chamber 804 may include manifolds 824-827.Manifolds 820-827 may be connected to subchambers of first chamber 802and second chamber 804, as shown in FIG. 18.

Product 800 may further include a main conduit with secondary conduitsconnected to the plurality of manifolds that supply pressurized fluid tochambers. As shown in the example of FIG. 18, product 800 may include amain conduit 806 with a secondary conduit 807 connected to manifold 820,a secondary conduit 808 connected to manifold 824, a secondary conduit809 connected to manifold 821, a secondary conduit 810 connected tomanifold 825, a secondary conduit 811 connected to manifold 822, asecondary conduit 812 connected to manifold 826, a secondary conduit 812connected to manifold 823, and a secondary conduit 814 connected tomanifold 827. Thus, when pressurized fluid is supplied via main conduit806, the pressurized fluid may then be distributed to secondary conduits807, 809, 811, 813, which in turn distribute the pressurized fluid tomanifolds 820-823 and then to subchambers 832 of first chamber 802.Similarly, pressurized fluid may be distributed to secondary conduits808, 810, 812, 814, which in turn distribute the pressurized fluid tomanifolds 824-827 and the subchambers of second chamber 804.

Providing a chamber with a plurality of manifolds may assist withfilling the subchambers of a chamber or groups of subchambers atdifferent pressures. If it is desired to provide subchambers or groupsof subchambers at various pressures, manifolds may be sealed to providea group of subchambers at a given pressure or individual connectionsbetween manifolds and subchambers may be sealed to provide subchambersat selected pressures. For example, pressurized fluid at a firstpressure may be supplied via main conduit 806 and secondary conduits807, 809, 811, 813 to manifolds 821-823 and subchambers 832 of firstchamber 802. If it is desired, for example, to provide subchambers 832connected to manifold 823 at the first pressure, a seal may be formedbetween manifold 823 and secondary conduit 813. Pressurized fluid at asecond, different pressure may then be supplied to manifolds 820-822 anda seal may then be formed between a selected manifold and a secondaryconduit to provide a second group of subchambers at a second pressure.This process may be repeated, as desired, to provide additional groupsof subchambers at different pressures.

Alternatively, individual seals may be provided between subchambers andtheir respective manifolds after supplying pressurized fluid at adesired pressure. For example, a first pressure may be supplied tomanifold 823 and subchambers 832 via secondary conduit 813 and a sealmay then be formed between subchamber 843 and manifold 823. Pressurizedfluid at a second pressure may then be supplied to manifold 823 andsubchambers 832 connected to manifold 823 and a seal may then be formedbetween one other subchambers 832 connected to manifold 832 and manifold823. Pressurized fluid at a third pressure may then be supplied tomanifold 823 and the remaining subchambers 832 connected to manifold823, and a seal may then be formed between one of the remainingsubchambers 822 and manifold 823. This process may be repeated for othersubchambers and other manifolds and their respective subchambers.

According to one configuration, a chamber 900 may include a firstmanifold 903 and a second manifold 905 that respectively supplypressurized fluid to a first group 902 of subchambers and a second groupof subchambers 904, as shown in FIG. 19. First manifold 903 and firstgroup 902 of subchambers may be arranged on lateral side 912 of chamber900, while second manifold 905 and second group 904 of subchambers maybe arranged on medial side 910 of chamber 900, as shown in FIG. 19.According to another example, either or both of first manifold 903 andsecond manifold 905 may be located between first group 902 ofsubchambers and second group 904 of subchambers instead of along themedial and lateral sides of chamber 900. According to one configuration,pressurized fluid at different pressures may be supplied to manifolds903, 905 so that first group 902 of subchambers and second group 904 ofsubchambers enclosed pressurized fluid at different pressures.

According to one configuration, subchambers of a chamber may extendsubstantially straight across a chamber in a medial to lateraldirection. Such a direction may be, for example, substantiallyperpendicular to a longitudinal axis of a chamber. According to anotherconfiguration, one or more subchambers of a chamber may be angledrelative to the medial to lateral direction. For example, one or moresubchambers 1012-1016 in a heel region 1006 of a chamber 1000 may beoriented at an angle 1020 relative to the medial to lateral directionextending between lateral side 1002 and medial side 1004 of chamber1000, as shown in the example of FIG. 20.

For instance, subchamber 1016 may extend substantially straight acrosschamber 1000 in a direction extending from lateral side 1002 to medialside 1004 of chamber. The extending direction of subchamber 1016 may besubstantially perpendicular to a longitudinal axis of chamber 1000 thatextends between the heel region 1006 and forefoot region 1010 of chamber1000. Conversely, subchamber 1013 may extend between lateral side 1002and medial side 1004 at angle 1020 relative to the direction thatsubchamber 1016 extends between lateral side 1002 and medial side 1004.Angle 1020 may vary from subchamber to subchamber or may besubstantially the same from subchamber to subchamber. Angle 1020 may be,for example, approximately 10-60°.

According to one configuration, any of subchambers 1012, 1014, 1015, and1016 may also extend at an angle relative a generally straight directionbetween lateral side 1002 and medial side 1004 of chamber 1000. Theangle at which subchambers 1012, 1014, 1015, 1016 are oriented may fallwithin the range of approximately 10-60°, like angle 1020. As shown inthe example of FIG. 20, the angles at which subchambers 1012-1016 areangled relative to a generally straight direction between lateral side1002 and medial side 1004 of chamber 1000 may vary from subchamber tosubchamber. For instance, the angle at which subchambers 1012-1016 areoriented relative to a generally straight direction between lateral side1002 and medial side 1004 of chamber 1000 may decrease from subchamber1012 to subchamber 1016, as shown in FIG. 20, with subchamber 1012 beingoriented at the largest angle and subchamber 1016 being substantiallyoriented along the generally straight direction between lateral side1002 and medial side 1004 of chamber 1000. According to oneconfiguration, midfoot region 1008 and/or forefoot region 1010 may alsoinclude one or more angled subchambers, like subchambers 1012-1015 ofheel region 1006 in FIG. 20.

Providing one or more angled tubes may provide support for a foot of afootwear wearer who experiences pronation during movement. For example,when an article of footwear including chamber 1000 is planted on aground surface during movement of a wearer who experiences pronation,the lateral side 1002 of heel region 1006 may strike a ground surfacefirst. As the wearer moves forward, the footwear would roll forwardtowards midfoot region 1008 and forefoot region, but the footwear wouldalso pronate from lateral side 1002 to medial side 1004. Because of themovement from lateral side 1002 to medial side 1004 due to pronation,angled subchambers may advantageously provide enhanced support to a footduring pronation, such as by being generally aligned with the rollingmovement of a wearer's foot from heel to forefoot and the pronatingmovement of a wearer's foot from lateral side to medial side. Forinstance, subchambers 1012-1016 in heel region 1006 of chamber 1000 maybe progressively oriented at an angle relative to a generally straightdirection between lateral side 1002 and medial side 1004 of chamber 1000towards the heel of chamber, as shown in FIG. 20, so that as the footrolls forward and pronates from lateral side 1002 to medial side 1004,subchambers 1012-1016 will have orientations and positions correspondingto the movement of the foot.

Chambers described herein may include a upper barrier layer and a lowerbarrier layer that are substantially impermeable to a pressurized fluidcontained by the chamber. For example, sheet 400 and sheet 402 shown inthe molding process depicted in FIGS. 9 and 10, may respectively serveas an upper barrier layer and a lower barrier layer. The upper barrierlayer and the lower barrier layer may be provided as sheets having thesame thickness or different thicknesses. For example, each of upperbarrier layer and lower barrier layer may have a thickness ofapproximately 0.060 to 0.40 inches (approximately 1.5 to 10 mm). Inanother example, each of upper barrier layer and lower barrier layer mayhave a thickness of approximately 0.10 to 0.30 inches (approximately 2.5to 7.6 mm). In another example, each of upper barrier layer and lowerbarrier layer may have a thickness of approximately 0.020 to 0.030inches (approximately 0.50 to 0.76 mm). In another example, each ofupper barrier layer and lower barrier layer may have a thickness ofapproximately 0.025 inches (approximately 0.64 mm).

Upper barrier layer and lower barrier layer are bonded together aroundtheir respective peripheries to form a peripheral bond, such as bondedregion 170 of chamber 130, and cooperatively form a sealed chamber inwhich the pressurized fluid is located. The pressurized fluid containedby chamber 130 may induce an outward force upon barrier layers thattends to separate or otherwise press outward upon barrier layers,thereby distending barrier layers, such as to form subchambers 131-143,connections 151-163, and manifold 150. In order to restrict the degreeof outwardly-directed swelling (i.e., distension) of barrier layers dueto the outward force of the pressurized fluid, bonded region 170 isformed between barrier layers.

Fluid-filled chamber 130 may also provide a midsole in combination withother materials or components, such as, for example, a polymer foammaterial, such as polyurethane or ethylvinylacetate, which mayencapsulate the fluid-filled chamber 130. Such a foam material may forma sidewall of the midsole. In addition to the polymer foam material andfluid-filled chamber 130, a midsole may incorporate one or moreadditional footwear elements that enhance the comfort, performance, orground reaction force attenuation properties of footwear 100, includingplates, moderators, lasting elements, or motion control members, forexample. Although absent in some configurations, outer sole 140 issecured to a lower surface of upper 110 and may be formed from a rubbermaterial that provides a durable and wear-resistant surface for engagingthe ground.

A wide range of polymer materials may be utilized for the chambersdiscussed herein. In selecting materials for a chamber, engineeringproperties of the material (e.g., tensile strength, stretch properties,fatigue characteristics, dynamic modulus, and loss tangent) as well asthe ability of the material to prevent the diffusion of the fluidcontained by the chamber may be considered. When formed of thermoplasticurethane, for example, a chamber wall may have a thickness ofapproximately 1.0 millimeter, but the thickness may range from 0.2 to4.0 millimeters or more, for example. In addition to thermoplasticurethane, examples of polymer materials that may be suitable for achamber include polyurethane, polyester, polyester polyurethane, andpolyether polyurethane. Chamber 200 may also be formed from a materialthat includes alternating layers of thermoplastic polyurethane andethylene-vinyl alcohol copolymer, as disclosed in U.S. Pat. Nos.5,713,141 and 5,952,065 to Mitchell, et al. A variation upon thismaterial may also be utilized, wherein layers include ethylene-vinylalcohol copolymer, thermoplastic polyurethane, and a regrind material ofthe ethylene-vinyl alcohol copolymer and thermoplastic polyurethane.Another suitable material for a chamber is a flexible microlayermembrane that includes alternating layers of a gas barrier material andan elastomeric material, as disclosed in U.S. Pat. Nos. 6,082,025 and6,127,026 to Bonk, et al. Additional suitable materials are disclosed inU.S. Pat. Nos. 4,183,156 and 4,219,945 to Rudy. Further suitablematerials include thermoplastic films containing a crystalline material,as disclosed in U.S. Pat. Nos. 4,936,029 and 5,042,176 to Rudy, andpolyurethane including a polyester polyol, as disclosed in U.S. Pat.Nos. 6,013,340; 6,203,868; and 6,321,465 to Bonk, et al.

The fluid within a chamber may be pressurized between zero andthree-hundred-fifty kilopascals (i.e., approximately fifty-one poundsper square inch) or more. In addition to air and nitrogen, the fluid mayinclude octafluorapropane or be any of the gasses disclosed in U.S. Pat.No. 4,340,626 to Rudy, such as hexafluoroethane and sulfur hexafluoride.In some configurations, a chamber may incorporate a valve or otherstructure that permits the wearer to adjust the pressure of the fluid.

The invention is disclosed above and in the accompanying figures withreference to a variety of configurations. The purpose served by thedisclosure, however, is to provide an example of the various featuresand concepts related to the invention, not to limit the scope of theinvention. One skilled in the relevant art will recognize that numerousvariations and modifications may be made to the configurations describedabove without departing from the scope of the present invention, asdefined by the appended claims.

1. An article of footwear comprising: an upper forming a first portionof a void within the footwear; a sole structure secured to the upper,the sole structure including a depression that forms a second portion ofthe void; and a chamber that encloses a pressurized fluid, the chamberbeing located within the depression, and the chamber including aplurality of fluid-filled subchambers that extend in a medial to lateraldirection of the footwear, at least two of the subchambers beingisolated from fluid communication with each other.
 2. The article offootwear of claim 1, wherein the depression extends from a forefootregion to a heel region of the article of footwear, and the depressionextends from a lateral side to a medial side of the article of footwear.3. The article of footwear of claim 1, wherein the upper includes anankle opening and the chamber is removable through the ankle opening. 4.The article of footwear of claim 1, wherein the chamber includes amanifold fluidically-connected to at least one of the subchambers. 5.The article of footwear of claim 1, wherein the subchambers form amajority of the chamber.
 6. The article of footwear of claim 1, whereinthe subchambers are separated from one another in a direction extendingbetween a forefoot region and a heel region of the footwear.
 7. Thearticle of footwear of claim 6, wherein the subchambers are separatedfrom one another by portions of a bonded area that extends between alateral side and a medial side of the footwear.
 8. The article offootwear of claim 1, further comprising an insert located on a topsurface of the chamber.
 9. The article of footwear of claim 8, whereinthe insert extends along a periphery of the chamber.
 10. The article offootwear of claim 9, wherein the insert includes a foam material. 11.The article of footwear of claim 1, wherein one or more of thesubchambers are oriented at an angle relative to a direction extendingsubstantially straight across the chamber in a medial to lateraldirection.
 12. The article of footwear of claim 1, wherein the chamberincludes a plurality of manifolds.
 13. The article of footwear of claim12, wherein the plurality of manifolds includes a first manifoldfluidically-connected to a first group of the subchambers and a secondmanifold fluidically-connected to a second group of the subchambers, thefirst group of the subchambers and the second group of the subchambersenclosing the pressurized fluid at different pressures.
 14. The articleof footwear of claim 1, wherein the subchambers enclose the pressurizedfluid at different pressures.
 15. An article of footwear comprising: anupper forming a first portion of a void within the footwear, and theupper including an ankle opening that provides access to the void; asole structure secured to the upper, the sole structure including adepression that forms a second portion of the void; a chamber thatencloses a pressurized fluid, the chamber being located within thedepression; and an insert located on a top surface of the chamber andbeing at least partially formed from a polymer foam material, whereinthe chamber and the insert are removable from the void through the ankleopening.
 16. The article of footwear of claim 15, wherein the chamberincludes a plurality of subchambers that extend from a lateral side ofthe footwear to a medial side of the footwear, the subchambers beingseparated from each other by a bonded area of the chamber.
 17. Thearticle of footwear of claim 16, wherein the subchambers include a firstgroup of subchambers located in a heel region of the chamber and asecond group of subchambers located in a forefoot region of the chamber,the first group of subchambers enclosing the pressurized fluid at ahigher pressure than the second group of subchambers.
 18. A method ofmanufacturing a chamber enclosing a pressurized fluid, the methodcomprising: placing a first sheet and a second sheet within a mold;closing the mold to form a bonded area between the first sheet and thesecond sheet and at least one chamber, wherein the chamber includes aplurality of subchambers and a manifold fluidically-connected to atleast two of the subchambers; supplying a pressurized fluid at a firstpressure to the manifold so that the two subchambers are inflated withthe pressurized fluid; first sealing a connection fluidically-connectingthe manifold to a first subchamber of the two subchambers to seal thepressurized fluid within the first subchamber; supplying the pressurizedfluid at a second pressure to the manifold so that a second subchamberof the two subchambers is inflated with the pressurized fluid; andsecond sealing a connection fluidically-connecting the manifold to thesecond subchamber to seal the pressurized fluid within the secondsubchamber.
 19. The method of claim 18, wherein the first sealing stepincludes sealing connections to subchambers located within a forefootregion of the chamber and the second sealing step includes sealingconnections to subchambers located within a heel region of the chamber,wherein the subchambers located within the heel region of the chamberenclose pressurized fluid at a higher pressure than the subchamberslocated within the forefoot region.
 20. The method of claim 18, furthercomprising a second step of increasing the pressure of the pressurizedfluid supplied to the manifold to a third pressure greater than thefirst pressure and the second pressure after the second sealing step,and further including a third sealing step after the second step ofincreasing the pressure of the pressurized fluid; wherein the firstsealing step includes sealing connections to subchambers located withina midfoot region of the chamber; wherein the second sealing stepincludes sealing connections to subchambers located within a forefootregion of the chamber; wherein the third sealing step includes sealingconnections to subchambers located within a heel region of the chamber;and wherein the subchambers located within the heel region of thechamber enclose pressurized fluid at the third pressure, the subchamberslocated within the forefoot region enclose pressurized fluid at thesecond pressure, and the subchambers located within the midfoot regionenclose pressurized fluid at the first pressure.
 21. An article offootwear comprising: an upper forming a first portion of a void withinthe footwear, the upper including an ankle opening that provides accessto the void; a sole structure secured to the upper, the sole structureincluding a depression that forms a second portion of the void; and achamber that encloses a pressurized fluid, the chamber being locatedwithin the depression, the chamber including a plurality of fluid-filledsubchambers that extend in a medial to lateral direction of thefootwear, and the chamber including a manifold in fluid communicationwith the subchambers; wherein the chamber includes bonds that extend inthe medial to lateral direction and are located between the subchambers;wherein the chamber is removable from the article of footwear throughthe ankle opening.
 22. The article of footwear of claim 21, wherein thesubchambers include a first subchamber including the pressurized fluidat a first pressure and a second subchamber including the pressurizedfluid at a second pressure, wherein the first pressure is different fromthe second pressure.
 23. The article of footwear of claim 21, whereinone or more of the subchambers are oriented at an angle relative to adirection extending substantially straight across the chamber in themedial to lateral direction.
 24. The article of footwear of claim 21,further comprising an insert located on a top surface of the chamber.25. The article of footwear of claim 24, wherein the insert extendsalong a periphery of the chamber.